Those who oppose the $383 million development argue that the construction of the Gilder Center will intrude on the 17.58-acre public park, eliminate trees and cause environmental disruption near the building site. The new facility will increase the museum’s total land-use by a quarter of an acre.

“I don’t want to see this happen because we use the park,” said King at the rally. “They’re going to take trees down. These trees, some of them are over 100 years old. We don’t want that to happen. We want to save the park.”

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When asked about the protesters’ environmental concerns, a spokesperson from the museum told ALL ARTS that “while seven trees will be removed as part of the project, 22 new trees will be planted once construction is completed and the amount of publicly accessible open space in the Theodore Roosevelt Park will be increased.”

The group, represented by land-use lawyer Michael Hiller, responded to the court’s decision by filing a notice of appeal, to which the court granted an interim stay that prohibits the museum from conducting exterior work, including the removal of trees, until an official appeal decision is reached — though preparatory work inside of the museum continues.

The museum announced plans for the Gilder Center project expansion in 2014, citing the museum’s growing attendance — up from three million annually to five million — and the public’s increased interest in educational programming. The resulting proposal, designed by Studio Gang, imagines the Gilder Center as a connective tissue that will improve visitor flow through the museum’s various facilities while serving as a learning center and public exhibition space.

“The Gilder Center for Science, Education and Innovation will be a major new resource for science education for all New Yorkers and visitors from around the world,” said the museum in a statement. “The inherent value of this project is reflected in the broad public support it has received from numerous elected officials, neighborhood groups, and advocacy organizations. We have every expectation that the appellate court will affirm the Supreme Court decision.”

UPDATE:On Tuesday, Feb. 5, the appellate court lifted the interim stay on the Gilder Center Project, allowing the museum to proceed with all work.